Extension-ladder.



Patented July I, 1902.

c. H. scrmmaens EXTENSION LADDER.

(Application flied Mar. 22, 1902.)

(No Model.)

UNITED STATES ATENT QFFICE.

CHARLES H. SCHAMBERS, OF WARREN, PENNSYLVANIA.

EXTENSION-LADDER.

SPECIFICATION forming part of Letters Patent. No. 703,836, dated July 1,1902.

. Application filed March 22, 1902. Serial No. 99,526. (No model.)

a citizen of the United States, residing at Warren, in the county ofWarren and State of Pennsylvania, have invented a new and usefulExtension-Ladder, of which the following is a specification.

The invention relates to improvements in extension-ladders.

The object of the present invention is to improve the construction ofextension-ladders and to provide a simple and comparatively inexpensiveone adapted to support a staging for carpenters, painters, and the likeand capable of ready adjustment to arrange the staging at the desiredelevation and to enable the supporting portion to extend beneath deepcornices and the like.

The invention consists in the construction and novel combination andarrangement of parts hereinafter fully described, illustrated in theaccompanying drawings, and pointed out in the claims hereto appended.

In the drawings, Figure 1 is a perspective View of an extension-ladderconstructed in accordance with this invention. Fig.2 is an enlargedsectional view of the upper portion of the extension-ladder,illustrating the manner of mounting the adjustable bracket. Fig. 3 is anenlarged detail view illustrating the construction of the ratchetmechanism. Fig. 4: is a detail sectional view of one side of theextension-ladder, illustratingthe con-' struction of the Windlass orshaft of the slidable section of the ladder. Fig. 5 is a detail viewillustrating the manner of mounting the removable crank-handle.

Like numerals of reference designate corresponding parts in all thefigures of the drawings.

1 and 2 designate sections of an extensionladder, and the section 1,which is designed to rest on the ground orother support, has its sidesspread at the bottom to provide a broad base. The slidablesection2,which is arranged between the sides of the lower sec tion 1, is arrangedon the rungs thereof, and it is secured on the same by upper and lowerclamps 3 and 4:, located at the upper portion of the section 1 andcomposed each of a pair of arms 4. and 5 and a bar 6, hinged to one ofthe arms and detachably engaging the other. The bar 6 is provided at itsends with eyes 7 and 8, arranged betweeneyes 9 and 10 of the arms 1 and5 and hinged to the arm 4 by a pintle 11 and detachably secured to thearm 5 by a removable pin 12, secured to the adjacent side ofthe section1 by a short chain, as clearly shown in Fig. 1. The eyes of the arms-arearranged in pairs, and the arms extend outward beyond the outer edges ofthe side bars of the slidable section. The pins of the clamps areadapted to be readily removed to permit the arms 5 and the bars 6 to beseparated for removing one of the ladder-sections from the other forenabling the said sections to be used independently of each other or forany other purpose.

The slidable section is raised and lowered by a rope or cable 13 and aWindlass or shaft 14. The rope or cable 13 is secured at one end to thebottom rung of the slidable section,and it extends upward therefrom to apulley 15, mounted in a suitable block or support, which is suspendedfrom the top rung of the lower ladder-section, and the said rope orcable extends downward from the said pulley 15 to the shaft 14, which islocated a sufiicient distance above the lower end of the stationary .orbottom section of the ladder to enable it to be conveniently operated.The shaft is provided with a crank-handle 16, and it is locked by a pawland ratchet, hereinafter described. By rotating the shaft the slidablesection is raised and lowered, as will be readily understood. Each ofthe sections of the ladder is provided with a spur or projection at thelower end of each'of its side bars, and each spur or projection consistsof a bolt or pin 17, mounted in suitable guides or eyes 18 and providedwith an arm 19, arranged to engage projections 20 and 21. The bolt orpin is adapted to be rotated in the eyes or guides and when extended itsarm is engaged beneath the lower projection 20. The upper projection isadaptedto be engaged by the arm to support the pin or projection in anelevated position. The pin or bolt is adapted to-be embedded in theground or other support, and it will offectually prevent theladder-sections from slipping. H

Mounted upon the slidable section of the ladder is avertically-adjustable bracket 22,

composed of an approximately horizontal supporting portion, verticalslides Y23, and inclined braces 24. The slides, which extendlongitudinally of the side bars of the upper or extension section of theladder, are provided at their side edges with longitudinal flanges andare connected by crossed diagonal braces and by upper and lowertransverse bars 26 and 27, the upper transverse bar being an gularlybent adjacent to its ends and oifset from the plane of the outer edgesof the side bars of the extension-section for a purpose hereinafterdescribed. The horizontal or approximately horizontal portion of thebracket is adapted to receive the staging or platform, and it issupported by the said braces 24, which are flanged. The sides of thehorizontal supporting portion of the adjustable bracket are composed ofbars or sections 28 and 29, provided at their upper edges with .teeth orserrations to prevent the staging or platform from slipping and havingperforations arranged at intervals and adapted to receive fasteningdevices 30 and 31, whereby the bars or sections of the top or supportingportion of the bracket are secured in their adjusted position. Thehorizontal supporting portion of the bracket is adapted to be lengthenedor shortened to enable it to extend beneath deep cornices or the like,and a roller 32 is journaled between the ends of the side bars 31 and ispreferably covered by hard rubber or other suitable material and isadapted to engage the building or other structure. Instead of employinga smooth roller, as illustrated inFig. 1 of the accompanying drawings, aflanged bar or roller may be employed for enabling the latterto besupported against the uprights of a building before the same iscompleted. I

The side bars 30, which are rigid with the upright portions of theadjustable bracket, are also supported by crossed braces 33, secured tothe bars 30 at the lower edges thereof. The roller 32 is removablymounted in the bearings of the bars 31 by means of keys or othersuitable fastening devices to enable a flanged bar, as before described,to be used.

The adjustable bracket is supported by a rope or cable 34, passing overa pulley 35 of the extension-ladder section and secured at its ends toshafts or windlasses 36 and 37, mounted, respectively, on theextension-ladder section and on the bracket. The pulley 35 is mounted ina suitable block or casing,

which is suspended from the top rung of the extension-ladder section, asclearly shown in Fig. 1. The lower shaft 36, which is journaled insuitable bearings of the extensionsection of the ladder, is constructedsubstantially the same as the shaft or Windlass 14, with the exceptionthat the crank-handle 39 is removable.

The crank-handle 39 is provided with a threaded stem 39, arranged in athreaded socket 40 of the shaft 36 and adapted to permit thecrank-handle 39 to be removed when the latter is rotated backwardly tounscrew the threaded stem; but when the crank-handle is rotatedforwardly it will be firmly held on the shaft and will carry the samewith it. The crank-handle is adapted to be removed to permit the shaft36 to pass the clamps 3 and 4 to raise the extension-section to thelimit v of its upward movement, and such upward movement is limited bythe spurs or projectionsformed by the bolts or pins 17. When the movableor-extensiou section is raised to the limit of its movement, the spursor projections engage the lower clamp 4 and prevent a further upwardmovement of the said section, so that-there is no liability of acci- Thesuptions of the adjustable bracket, is composed of approximatelyL-shaped sides connected at their lower ends by a rung 43 and pivoted attheir upper ends to the upright portions of the bracket. The lowertransverse bar 27 has its ends bent outward to form arms 44, which areprovided at their outer sides with projec tions 45, arranged to beengaged by the pivoted support, whereby the rung 43 will be olfset fromthe ladder-section 2. The adjustable bracket is also provided at theinner face of the ladder-section 2 with upper and lower transverse bars26 and 27, and the shaft or windlass of the adj ustable bracket isadapted to be readily rotated to enable the bracket to be lowered by aperson standing on the rung 43-01: the support. The upper transverse bar26 is ofiset from the ladder-section to permit the hand of a personstanding upon the support to clear the rungs of the ladder as theadjustable bracket is lowered. The offset rung 43 and the side bars ofthe support 42 are also adapted to clear the upper and lower clamps inlowering the bracket to the top of the lower laddersection. The lowerladder section is shorter than the extension-ladder section to enablethe latter to be lowered to and rest upon the ground, and after this hasbeen done the clamps may be unfas'tened to release the lowerladder-section to permit the same to drop back against the building orIIOA wardly the pawl or dog is locked out of engagement with theratchet-wheel by the dog 47, as clearly shown in dotted lines in Fig. 3of the drawings. The dog 47 is preferably pivoted between its ends andits movement is limited by a stop 48, and it is provided with a suitablegrip or handle. If desired, however, the locking-dog may be pivoted atone end or consist of a single arm instead of a lever, as shown.

The ladder-sections are adapted to be used independently of each otherwhen desired, and they are capable of ready adjustment to arrange theadjustable bracket at any height, and the bracket is also capable ofadjustment both to raise and lower it and to vary the length of itshorizontal or supporting portion to position the parts properly withrelation to the building or other structure and to enable them tosupport a platform or staging of the desired width. The platform orstaging is supported by a pair of extension-ladders of the formillustrated in the accompanying drawings, and they may be connected by arope anchored to the ground or otherwise secured to prevent the stagingor platform from slewing or moving the ladders laterally.

What I claim is 1. In a device of the class described, the combinationof the ladder-sections 1 and 2, the section 2 being capable of movementlongitudinally of the section 1, the arms mounted on the section 1 andextending beyond the other section and provided With eyes, thelockingbars provided with eyes at their ends, the eyes at one side ofthe ladder being hinged to the eyes of the adjacent arms, and removablefastening devices engaging the eyes of the locking-bars and the arms atthe other side of the ladder, substantially as described.

2. In a device of the class described, the combination of aladder-section, an adjustable bracket slidably mounted on theladdersection and projecting therefrom at one side thereof, a supportdepending from the bracket at the opposite side of the ladder, andhoisting mechanism connected with the bracket and with theladder-section and having oper-v ating mechanism mounted on the bracketand located within reach from the support, substantially as described.

3. In a'device of the class described, the

arms having projections, a pivoted support composed of approximatelyL-shaped sides supported by the projections, and a rung connecting thesides, and atransverse bar located above the support and forming a gripor handle, substantially as described.

5. In a device of the class described, the combination of aladder-section, a verticallymovable support mounted on theladder-section and provided with an adjustable support ing portionhaving a roller for engaging a building, hoisting mechanism connectedwith the ladder-section and with the bracket and having shafts orwindlasses mounted on both of such parts, and a support carried by thebracket, substantially as described.

6. In a device of the class described, the combination of theladder-sections 1 and 2 detachably connected, an adjustable bracketmounted on the ladder-section 2, a lower hoisting mechanism connectingthe laddersections, an upper hoisting mechanism connecting the bracketwith the ladder-section 2 and provided at each end with means foroperating it, and a support carried by the bracket, substantially asdescribed.

In testimony that I claim the foregoing as my own I have hereto affixedmy signature in the presence of two witnesses.

CHARLES H. SOHAMBERS.

WVitnesses:

D. M. HOWARD, R. V. STONE.

